5 2 FLOWER-LAND. 



may find some oak apples. They are called galls, and 

 are caused first of all by a little fly, which makes a 

 hole under the skin of the oak, where it lays its eggs. 

 Some kinds of these galls are smaller, and quite 

 round and hard. You often see them with a little 

 round hole in them, which has been made by the grub 

 of the fly when it ate its way out of the little cell 

 where it was born. If we look at the wild rose 

 bushes we may find something of the same kind 

 there. They are a good size, and are covered with 

 hairs which are often coloured red. 



The galls of an oak which grows in Asia Minor 

 are used for making ink. Have you ever seen, in the 

 woods, great piles of oak bark ? It is used for tan- 

 ning leather ; and there are oaks which grow in 

 France and Spain, of which the bark supplies what 

 we know as cork. 



But the grasses, and the dandelion, and the nettle, 

 and the oak have reminded us of the uses of plants, 

 not only for food, or clothing, or medicine, but in very 

 many other ways. This is a very important part of 

 Botany, and you will find it full of interest. 



You will notice also how different plants grow in 

 different soils ; and this kind of knowledge is useful to 

 the gardener, the farmer, and the geologist. 



A. collection of dried plants is very useful to a 

 Botanist, and, if you are fond of Botany, you will 

 probably like to make one for yourself. In case you 

 should do so, I shall add a few hints in a postscript to 

 this short chapter. 



